pin down

US /pɪn daʊn/
UK /pɪn daʊn/
"pin down" picture
1.

identificar, definir

to understand or describe something exactly

:
It's hard to pin down the exact cause of the problem.
É difícil identificar a causa exata do problema.
I can't quite pin down what's bothering me.
Não consigo identificar exatamente o que me incomoda.
2.

imobilizar, prender

to make someone stay in a particular place or prevent them from moving

:
The police managed to pin down the suspect in the alley.
A polícia conseguiu imobilizar o suspeito no beco.
The heavy rain pinned us down in the cabin for hours.
A chuva forte nos prendeu na cabana por horas.